The present invention relates to the field of bowling alleys, and discloses a structure which has a longer useful life than any of the bowling alleys of the prior art.
Bowling alleys generally include lanes formed from a large number of narrow boards, the boards being held firmly together to define the bowling surface. A typical bowling lane is constructed of boards having a width of approximately one inch, and a regulation bowling lane is about 41.5 inches wide. Generally, the boards forming the first fifteen feet of the lane are made of hard maple, with the balance of the boards of the lane being constructed of long leaf yellow pine. In this specification, the term "lane" will be used to refer to the bowling surface, i.e. the boards described above, and the term "alley" will be used to refer to the entire structure, including the support means for the lane.
Bowling alleys having lanes formed of a plurality of narrow boards have been known for many years. One example of such an alley is shown in U.S. Pat. No. 631,090. The latter patent shows a group of boards or strips, interlocked with each other by a tongue-and-groove construction, and held firmly together by a series of metallic clamps. A similar idea is shown in U.S. Pat. No. 1,697,800, which also provides some vertical adjustability of the bowling surface, through the use of screws located below the surface. U.S. Pat. No. 1,795,624 also discloses a bowling alley constructed from a plurality of narrow boards. And U.S. Pat. No. 1,511,696 discloses still another bowling alley of the same general type, the boards of the bowling lane being held together by a combination of bolts and nails.
One major problem in the maintenance of bowling alleys results from the fact that wood absorbs moisture. As the boards forming the bowling lane absorb moisture from the surrounding air, they expand, especially in the transverse direction. The boards later contract when the humidity decreases. If the boards are nailed in place, as is true with most of the bowling lanes presently in use, the expansion causes the boards to separate, forming gaps between adjacent boards. Then, when a bowling ball strikes an edge of one of these boards, a piece of the wood is likely to chip off. This process of chipping is known as "feathering". Feathering can ruin a bowling lane in a relatively short time. The lane is left with crevices, pock marks, and generally undesirable surface features. This damage is quite apparent, even to the untrained eye.
Even if the boards of the lane are not nailed in place, absorption of moisture can be problematic. Expansion of the boards can cause the lane to break the clamp, or other holding device, which presses the boards together. And if the clamp does not break, then the edge of the lane may buckle, to accommodate the extra pressure, creating an unwanted slant in the lane surface. Also, the boards may be compressed beyond their elastic limit, so that gaps will form when the humidity is reduced. Such gaps in the lane are likely to cause feathering, as described above.
The issue of damage to a bowling lane due to expansion and contraction of the boards is not just an aesthetic problem. A bowling lane having visible gaps is likely to cause unpredictable and unwanted irregularities in the motion of the bowling ball. Bowling alleys are precisely crafted structures which must meet the standards set by the American Bowling Congress (ABC), which annually inspects bowling alleys throughout the country. If an alley does not pass the inspection, the alley cannot be used for official league and tournament play. Among many other items, an ABC inspection includes an examination of the surfaces of each lane. A spirit level is used to check for crosswise tilt and depressions, and a maximum tolerance of 0.040 inches is permitted.
Even if the bowling lane does not suffer from the effects of changes in humidity, it still suffers damage from normal use. The constant impacts of the bowling balls on the lanes produce small depressions, which eventually must be repaired. The surface of the lane can be sanded down, and sanding is usually done about once every three years. The sanding operation can remove from one-sixteenth to one quarter of an inch from the lane.
Sanding of the lane creates its own problems. Because the area near the foul line does not normally suffer much damage due to impact from a bowling ball, this area is not usually sanded. But the repeated sanding of the remainder of the lane creates a slope in the lane. Eventually, the amount of the slope becomes unacceptable, and the lane cannot be sanded further. When this point is reached, it would be helpful to be able to invert the lane, so as to begin again with the surface which originally faced downward. But if, as is true in many of the structures of the prior art, the boards are nailed into their supporting structure, it is impossible to use the underside of the boards in this way.
When a bowling lane which has been damaged by feathering or by repeated impacts of a bowling ball can be sanded no more, it is necessary to replace the lane. This is an expensive undertaking. It currently costs several thousand dollars to replace one lane. The cost of replacing an entire set of lanes is therefore prohibitively high, even for a moderately sized bowling establishment.
It is possible to address the moisture problem by impregnating the boards with a glycol-type solution which extracts all moisture and air from the wood. This method will eliminate moisture from the boards, but the method is also very expensive. It is also possible to seal the individual boards against moisture with polyurethane, or another sealing material, but this procedure is also very expensive, and is not completely effective.
The present invention solves the problems described above, and provides an economical structure for a bowling alley, the alley having a greatly increased life expectancy, compared with the bolwing alleys of the prior art. The invention also facilitates the inversion of the boards of the lane, so that when one side if finally exhausted, it is possible and practical to use the previously unused surface of the lane. The invention also makes it easy to raise and lower parts of the lane so as to maintain the level character of the lane.